Electric-pump governor.



PATENTED OCT. 30, 1906 v E. H. DEWSON. ELECTRIC PUMP GOVERNOR.

APPLICATION FILED AUG.22. 905.

' INVENTOR Ewan! @wmm arn EDWARD n. IDEWSON, or nnei woonieenn,PENNSYLVANIA. ASS1GN R" TO THE wssrmenonsn AIR: BRAKE cor/Irena, orrirrssnse, Penn VSYLVANIA A oonnonnrion'orrnnnsrmn ina.

ELEOTRiC PUMP. GOVERNOR.

' Specification of Iietters Patent.

- Patented Oct. so. leo' o Applioation filed August 22, 1965. Serial No.275,274.

To all whom, it may concern.-

Be it known that I, EnwAnn H. Dnwson,

a citizen of the- United States, residing in Edgewood Park, county ofAllegheny, and

3 State of Pennsylvania; have invented certain new and usefulImprovements in Electric Pump Governors, of which the following is aspecification.

This invention-relates to governors for elec re trically-operated pumps,and has for its object to provide improved means for. adjusting therange of pressures within which the ov ernor is adapted to open andclose the'ci'r uit.

sure from the pumpactlng upon the pistonand tending to open the.electric circuit, whereby' when the pump-pressure increases 2 to a ointsuflicient to overcome the 001m 'bine force of the spring andelectromagnet the armature moves away from the magnet, therebydiminishing its force, so that the piston then operates the switch witha positive 3o snap-like action. WVith such a construction it is oftendesirable to adjust the strength. of

- pull or the holding power of the electromag net to meet diiierentconditions of service, and my inventlon comprises means iorth1s purpose.Various devlces may be devised for securing this result; but I prefer toemploy means for adjusting the relative position of the poles of themagnet whereby. a.

resented for greater or lesser area may be y vary the 4'0 the magneticflux, and there strength'of pull of the magnet.

I will now describe morein detail a pre ferred form oistructur'eembodying my invention, reference being had to the accompa- 5 nyingdrawings, in which I g Figure 1 is a longitudinal section Fig. 2, a planview; Fig. 3, a transverse section talren on the line m 00 of Figs. 1and 2 and looking toward the right, and Fig. 4 a similar transversesection'in the same plane looking towvard the left As shown, thisconstruction comprises a bed-plate 3,having upright portions 4 and 5,

the former supporting a cylinder 1, having a Ac cured to the cross-head16 and covers the coil 1.0 of the electromagnet, the forward end ofchamber 6, containing piston 7 which is sub '5 5 ect to thepump-pressure by means of an in- Supported onopposite sides of theupright pieces are two threaded rods or bolts 17 on which is'rnountedthe adjustable cross-bar 6o 15. The rear head 20, which is secured tothe cylinder by bolts 18, is provided with a hollow core, 2, extendingaround theiston-rod 9 and carrying the coil 10 of the e ectroma net, thepiston-rod being adapted to slide through the core 2 and provided with across-head 16, which is rotatably mounted on the piston-rod, butniova-ble longitudinally therewith. A cylindrical casing 11 is sethecasing being rotatably mounted in a cross-bar or ring'12, slidinglysupported on the side rods 17 and having a set'escrew 13 to prevent thecasing from turning-after being clamped in acertain position. Y The endof the casin 11 is provided with an annular projecting anger 23 withcut-out portion-1,2 1 while the cylinder-head 20 has correspondingraised flange 21 with cut-out portions 22.' As will be readily seen fromthe drawings, these flanges 21 and 23 form the opposite poles of theelectromagnet, and when the'notches or cut-out portions-22 and 24 of theopposite poles are adjusted to register with each other, .as indicatedin Fig. 2, the flanges 21 and 23 make contact over their' maximum areaor surface. By partially ro tating the'casing 11 in the ring 12-andclamping the set-screw 13 the sections of the flange 23 may be adjustedtoregister partially'with the oppositeflange-sections and notchedsections, so as to give any desired amount of area of the opposite polesin contact, and thereby vary the cross-sectional area of the path of themagnet flux and the corresponding holding power of the magnet. A spring.14 is located between the adjustable crossbar 15 and the ring 12, whichmoves longitudinally with the piston and piston-rod. :31 00 Any desiredform of controlling device operated by the piston or movable abutmentmaybe employed for governing the motor, such as a switch for opening andclosing the electric circuit, that shown comprising a rockshaft- 26, arm25, and two flexible blades 27,

adapted to make contact with the terminals QElendBO. Ablow-outmagnet-coil 28 may be mounted between these terminals. The spring ltbeing adjusted to the desired tension andthe relative position of the polesof the elertiomagnet being set for a certain holding power, the switchis closed and the pump continues to operate until the pressure admittedat inlet 8 and acting on the piston. '7 is sufficient to overcome thepower of both spring and magnet. As soon as the piston begins to moveout the poles 21 and 23 of the magnet separate, and consequently as thepull of the magnet diminishes very rapidly as the poles separate thepiston moves with a ,positive and quick movement to the end of itsstroke, compressing the sprii'ig 14: and turning the rock-shaft 26 toopen the switch and stop the pump. The instant that the blades 27 leavethe terminal points the circuit through the coil 10 is broken, so thatthe magnet has no further power until the circuit is again closed. Asthe pressure on the piston then diminishes to a degree less than thepower of the spring, the piston-rod with its cross-head 16 and casing11, carrying the pole of the magnet, move back slowly to a point atwhich the blades 27 touch the terminals. This closes the circuit throughthe coil 10 and energizes the electromagnet, so that the poles areinstantly attracted and oper ate to complete the closing movement of thepiston-rod and switch. It will thus be seen that the degree of pressureat which the switch closes is determined by the spring, while theopening pressure is determined by the combined force of the spring andthe holding power of the electromagnet. This range of the governolgorthe difference between the degrees of opening and closing pressures, maybe adjusted to any amount desired by setting the'poles of the magnet tothe corresponding relative position, and thereby vary the pullor'holding power of the magnet. By means of this construction the rangeof the governor may be readily adjusted to meet different conditions,thereby gi ing very reliable and eflicient service.

Havmg now described my invention, what I I claim as new, and desire tosecure by Letters Patent, is

1. An electric-pressure governor comprising a movable abutment subjectto the fluidressure, a controlling device operated therey, anelectromagnet for opposing the fluidpressure, and means for adjustingthe holdmg power of the magnet.

2. An electric-pressure governor com ris ing a movable abutment subjectto the uidpressure, a controlling device operated there'- by, anelectromagnet for opposing the fluidpressure, and means for adjustingthe relative positions of the opposite poles of the magnet to vary itseffect.

3. An electric-pressure governor comprising a piston subject to thepump-pressure, a controlling device operated by the piston, an

adjustable spring opposing said pressure, an'

electro'magnet exerting its pull to assist the spring, and means foradjusting the holding power of said magnet.

4. An electric-pressure governor comprising a piston subject to thepump-pressure, a controlling device operated by the piston, anadjustable's 'n'ing opposing said pressure, an electromagnet exertingits pull to assist the spring, and means for adjusting the relativepositions of the opposite poles of the magnet to vary the range of thegovernor.

5. An electric-pressure governor comprising a piston subject to thepump-pressure and a controlling device operated thereby, anelectromagnet for opposing the fluid-pres sure, and means for adjustingthe area of the engaging surface of the opposite poles of the magnet.

65. An electric-pressure governor comprising a piston subject to thepump-pressure, an electric switch operated thereby to open and close themotor-circuit, an adjustable spring for opposing thefluidpressure, .anelectromagnet arranged concentrically with the piston-rod for assistingsaid spring, and means for adjusting the effective area of the poles ofthe magnet.

7. An electric-pressure governor comprising a piston subject to thepump-pressure, an electric switch operated thereby to open and close themotor-circuit, an adjustable spring for opposing the fluid-pressure, anelectromagnet arranged concentrically with the piston-rod for assistingsaid spring, and a casing forming part of said magnet surrounding theoil and rotatably mounted on the piston-rod.

1n testimony whereof I ha. re hereunto set my hand.

EDWARD H. DEWSON. Witnesses:

E. A. WRIGHT, J. B. lllACDONALD.

